Special Report: One little girl desperately wanted to be a YouTube star. Her brother adored football and his favourite player, Cristiano Ronaldo. Their cousin was a teenage electronics wiz. Since the start of Israel’s offensive in Gaza, more than 7,000 children have been killed in airstrikes, artillery and mortar fire. Often entire families disappeared in an instant. Here are the stories of nine Palestinian children who’ve been killed in the war, as told to Richard Hall and Ariana Baio